LTC3528B Linear Technology Corporation, LTC3528B Datasheet
LTC3528B
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LTC3528B Summary of contents
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... Additional features include a low shutdown current, open-drain power good output, short- circuit protection and thermal overload protection. The LTC3528/LTC3528B are offered in an 8-lead 3mm × 2mm × 0.75mm DFN package. Corporation. All other trademarks are the property of their respective owners. ...
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... TAPE AND REEL LTC3528EDDB#PBF LTC3528EDDB#TRPBF LTC3528BEDDB#PBF LTC3528BEDDB#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based fi nish parts. For more information on lead free part marking, go to: For more information on tape and reel specifi cations, go to: ELECTRICAL CHARACTERISTICS temperature range of – ...
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... POWER LOSS 1.5V IN 0.01 10 100 1 1000 LOAD CURRENT (mA) 3528 G01 LTC3528/LTC3528B = 1.2V 3.3V, unless otherwise noted. IN OUT MIN TYP 0.88 0.3 –7 –10 0.05 0.05 0. 25°C unless otherwise noted) A Effi ciency vs Load Current and V IN for (LTC3528) OUT 100 1000 ...
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... LTC3528/LTC3528B TYPICAL PERFORMANCE CHARACTERISTICS Effi ciency vs Load Current and V for V = 3.3V (LTC3528) OUT 100 EFFICIENCY POWER 60 LOSS www.DataSheet4U.com 0.01 0 LOAD CURRENT (mA) Maximum Output Current vs V 800 700 600 500 400 300 200 100 0 1 1 (V) IN Burst Mode Threshold Current ...
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... TEMPERATURE (°C) 3528 G14 Burst Mode Quiescent Current vs V (LTC3528) OUT 13 1.2V IN 12.5 11.5 10 (V) OUT 3528 G17 LTC3528/LTC3528B (T = 25°C unless otherwise noted DS(ON) OUT 450 = 3V OUT 400 350 300 PMOS 250 200 NMOS 150 100 1.5 2 2 ...
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... LTC3528/LTC3528B TYPICAL PERFORMANCE CHARACTERISTICS Burst Mode Waveforms V OUT 20mV/DIV INDUCTOR CURRENT 100mA/DIV www.DataSheet4U.com V = 3.6V 5μs/DIV OUT C = 22μF OUT C = 33pF 30mA LOAD Load Step Response (Burst Mode Operation, 3.6V to 5V, LTC3528) V OUT 100mV/DIV LOAD CURRENT 200mA/DIV V = 3.6V 50μs/DIV ...
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... COMP V V REF REF PK UVLO UVLO I ZERO START-UP LOGIC CLK 1MHz OSC + V – 10% REF – FB TSD THERMAL SHUTDOWN PGND SGND 6 7 LTC3528/LTC3528B 5 SW WELL SWITCH V OUT FB + – I ZERO COMP Σ SLOPE PK COMP – + ERROR AMP SLEEP COMP + V REF MODE – CONTROL FB ...
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... LOW NOISE FIXED FREQUENCY OPERATION Soft-Start The LTC3528/LTC3528B contains internal circuitry to pro- vide soft-start operation. The internal soft-start circuitry 8 slowly ramps the peak inductor current from zero to its peak value of 1.5A (typical), allowing start-up into heavy loads ...
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... Burst Mode operation is inhibited during start-up and until soft-start is done and V than The LTC3528B features continuous PWM operation at 1MHz. At very light loads, the LTC3528B will exhibit pulse-skip operation. LTC3528/LTC3528B . The load at which Burst Mode operation IN OUT is at least 0.24V greater OUT ...
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... OUT that this defeats the output disconnect and short-circuit protection features. PCB LAYOUT GUIDELINES The high speed operation of the LTC3528/LTC3528B de- mands careful attention to board layout. A careless layout will not produce the advertised performance. Figure 1 shows the recommended component placement. A large ground copper area with the package backside metal pad 10 properly soldered will help to lower the chip temperature ...
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... Molded chokes and some chip inductors usually do not have enough core area to www.DataSheet4U.com support the peak inductor currents of 1.5A seen on the LTC3528/LTC3528B. To minimize radiated noise, use a shielded inductor. See Table 1 for suggested components and suppliers. Table 1. Recommended Inductors ...
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... LTC3528/LTC3528B TYPICAL APPLICATIONS 1 Cell to 1.8V 4.7μ 0.88V TO 1.6V 4.7μF LTC3528 PGOOD SHDN OFF ON www.DataSheet4U.com Dual 1 Cell to 1.8V, 3V Sequenced Supply V IN 0.88V TO 1.6V 475k 4.7μF OFF ON 4.7μ OUT 1.8V V OUT 250mA 33pF 499k FB 10μF 1M GND 3528 TA02a 4.7μ OUT1 V V 1.8V IN OUT ...
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... OFF ON GND SW V OUT 3.3V V OUT 200mA 33pF 499k FB 10μF 287k 3528 TA04a V OUT V 3.3V OUT 400mA 499k 33pF 10μF FB 287k 3528 TA05a LTC3528/LTC3528B Effi ciency 100 0.01 0 100 1000 LOAD CURRENT (mA) 3528 TA04b Effi ciency ...
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... LTC3528/LTC3528B TYPICAL APPLICATIONS 2 Cell to 5V 4.7μ 1.8V TO 3.2V 4.7μF OFF ON www.DataSheet4U.com Li-Ion to 5V 4.7μ 2.7V TO 4.2V 4.7μF OFF OUT OUT 300mA LTC3528 1M PGOOD FB 22μF SHDN 316k GND 3528 TA06a SW V OUT OUT 400mA LTC3528 1M PGOOD FB 22μF ...
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... SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. LTC3528/LTC3528B R = 0.115 0.40 ± 0.10 TYP ...
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... LTC3528/LTC3528B RELATED PARTS PART NUMBER DESCRIPTION LTC3400/LTC3400B 600mA I DC/DC Converters LTC3401 3MHz, Synchronous Step-Up DC/DC Converter SW LTC3402 3MHz, Synchronous Step-Up DC/DC Converter SW LTC3421 3MHz, Synchronous Step-Up DC/DC Converter SW with Output Disconnect LTC3422 1.5A I www.DataSheet4U.com SW with Output Disconnect LTC3423/LTC3424 1A/ Converter LTC3426 1.2MHz, Step-Up DC/DC Converter ...